logLikExtHyp: log of Extended Hypergeometric Likelihiood at (X, mA,mB,N, alpha)
Description
This function calculates the logarithm of the Extended Hypergeometric likelihood at specified x and alpha, with marginal totals mA, mB, N fixed.
Usage
logLikExtHyp(x, marg, alpha)
Value
scalar loglikelihood value
Arguments
x
integer co-occurrence count that should properly fall within the closed interval [max(0,mA+mB-N), min(mA,mB)]
marg
a 3-entry integer vector (mA,mB,N) consisting of the first row and column totals and the table total for a 2x2 contingency table
alpha
a real number, the log odds ratio or affinity parameter for the 2x2 contingency table
Author
Eric Slud
Details
This is simply the logarithm of the Extended Hypergeometric (Harkness 1965) or Fisher noncentral Hypergeometric, as calculated by the R package BiasedUrn. The formula is log(pFNCHypergeo(x,mA,N-mA,mB,exp(alpha))
References
Fog, A. (2015), BiasedUrn: Biased Urn Model Distributions. R package version 1.07.
Harkness, W. (1965), “Properties of the extended hypergeometric distribution“, Annals of Mathematical Statistics, 36, 938-945.